Summary=======Some good results but some 3.x kernels were bad and this varied betweenmachines. In some, 3.1 and 3.2 were particularly bad. 3.4 regressed onone machine with a large amount of memory.

Benchmark notes===============mkfs was run on system startup. No attempt was made to age it. Nospecial mkfs or mount options were used.

The size parameter for tiobench was 2*RAM. This is barely sufficient for this particular test where the size parameter should be multiple times the size of memory. The running time of the benchmark is already excessive and this is not likely to be changed.

===========================================================Machine: arnoldResult: http://www.csn.ul.ie/~mel/postings/mmtests-20120424/global-dhp__io-threaded-ext3/arnold/comparison.htmlArch: x86CPUs: 1 socket, 2 threadsModel: Pentium 4Disk: Single Rotary Disk==========================================================tiobench-------- This has regressed in almost all cases although for this machine the main damage was between 2.6.32 and 2.6.34. 3.2.9 performed particularly badly. It's interesting to note that 3.1 and 3.2 kernels both swapped and unexpected swapping has been seen in other tests.==========================================================Machine: hydraResult: http://www.csn.ul.ie/~mel/postings/mmtests-20120424/global-dhp__io-threaded-ext3/hydra/comparison.htmlArch: x86-64CPUs: 1 socket, 4 threadsModel: AMD Phenom II X4 940Disk: Single Rotary Disk==========================================================tiobench-------- This is a mixed bag. For low numbers of clients, throughput on sequential reads has improved with the exception of 3.2.9 which was a disaster. For larger number of clients, it is a mix of gains and losses. This could be due to weakness in the methodology due to both a small filesize and a small number of iterations. Random read has improved.

With the exception of 3.2.9, sequential writes have generally improved.

Random write has a number of regressions and 3.2.9 is a diaster.

Kernels 3.1 and 3.2 had unexpected swapping.

==========================================================Machine: sandyResult: http://www.csn.ul.ie/~mel/postings/mmtests-20120424/global-dhp__io-threaded-ext3/sandy/comparison.htmlArch: x86-64CPUs: 1 socket, 8 threadsModel: Intel Core i7-2600Disk: Single Rotary Disk==========================================================tiobench-------- Like hydra, sequential reads were generally better for low numbers of clients. 3.4 is notable in that it regressed. Unlike hydra, 3.1 was the first bad kernel for sequential reads unlikely hydra where it was 3.2. There are differences in the memory sizes and therefore the filesize and it implies that there is not a single cause of the regression.

Random read has improved.

Sequential writes have generally improved although it is interesting to note that 3.1 was a kernel that regressed. 3.4 is better than 2.6.32 but it is interesting to note that it has regressed in comparison to 3.3.